ZINC STATUS AND INTERLEUKIN-1 BETA-INDUCED ALTERATIONS IN MINERAL METABOLISM IN RATS

Changes in zinc (Zn) metabolism and interleukin-1 beta (IL-1 beta) rel ease occur as part of the physiological response to tissue injury and trauma. In the present study, the influence of Zn status on the respon se to continuous low-dose IL-1 beta administration was evaluated. Rats were fed 50 mu g Zn/g (adequate zinc; AZn) or 5 mu g Zn/g (marginal z inc; MZn) diets for 14 days. On day 15, rats were infused via osmotic minipumps, with IL-1 beta (2.3 ng/hr) or saline (control, C) and eutha nized 1, 3, or 7 days later. In the AZn rats, IL-1 beta infusion resul ted in increased plasma copper (Cu) concentrations and ceruloplasmin ( Cp) activity, and decreased iron (Fe) concentrations throughout the 7d period. These effects were most pronounced on dl and d3. A similar tr end was observed in the MZn rats, but IL-1 beta-induced increases in p lasma Cu and Cp activity were less than in the AZn fed rats. In MZn an d AZn IL-1 beta infused rats, plasma Zn was decreased on Day 1, and Da y 3, respectively, compared with their respective controls. AZn IL-1 b eta-infused rats were characterized by high liver Fe, Zn, and metallot hionein (MT) concentrations on Day 1; by Day 7, only MT concentrations remained elevated. Liver MnSOD activity was 13%-29% higher in both th e AZn- and MZn-IL-1 beta-infused rats than their respective controls o n Day 3 and Day 7, with most significant increase observed on Day 7. T hese data show that Zn status can influence the response to low-dose I L-1 beta; this influence of 70 should be considered when IL-1 beta